Socket for incandescent lamps.



No. 690,976. Patented Ian. l4, I902. N. MARSHALL.

SOCKET FOR INCANDESGENT LAMPS.

(Application filed Aug. 8, 1900.)

(No Model.)

' are effectively MARSHALL-SANDERS COMPANY, OF

CORPORATION OF MAINE.

BOSTON, MASSACHUSETTS, A

SOCKET FOR INCANDESCENT LAlViPS.

SPECIFICATION forming part of Letters Patent No. 690,976, dated January 14, 1902. Application filed August 8, 1900. Serial No. 26.284. (No model.)

To ctZZ whom, it may concern.-

Be it known that I, NORMAN MARSHALL, a citizen of the United States, residing at Newton, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Sockets for Incandescent Lamps, of which the following is a specification, reference being bad therein to the accompanying drawings.

My invention relates to improvements in sockets for incandescent lamps.

The object of my invention is to provide a socket in which the current-carrying parts insulated from the metallic outer shell under all conditions, in which the wire contacts are easily accessible, and in which the circuit-breaking mechanism is effective and durable for high voltages, and at the 'same time cheaply made, with the least opportunity for defects of manufacture. I obtain these results by the mechanism illustrated by the accompanying drawings and described in the following specification.

Figure'l is a side view of my improved socket with the shell removed and the insulating-ears L L partly open. Fig. 2 is a similar View facing one wire terminal G and with part of the insulating-ring A and lamp-terminal D cut away and the insulating-ear L thrown back in position for connecting the conducting-Wire. Fig. 3 is a similar view facing the opposite terminal G. Fig. 4 is an end View of Fig. 1, showing the flexible inner lamp-terminal and terminal insulating-ears L L. Fig. 5 is a half side View and a halfsection of the metallic shell and cap and detail of the screw and nut formed into the shell for holding cap and shell together. Fig. 6 is an end view of Fig. 3 with the cord removed, showing the central recess and circuit-breaking mechanism therein and the two large cord-holes I I. Fig. 7 is a section through the center of the porcelain socket-body and circuit-breaking mechanism and lamp-contacts, showing these parts, dotted lines on the tip and key representing the mechanism in its-off position. Fig. 8 is a detail of the flexible insulating-earpiece as it is stamped out for insulating the wire contacts and other parts from the outer shell. Fig. 9 is a part section on line a a, Fig. 6, showing the opening from the hole I to the contact recess E and the screw-shell fastening (Z and threaded eyelet V. Fig. 10 is a view showing a keyless socket.

Referring to Figs. 1, 2, 3, 4, 5, and 6, B is a body or case, preferably of pottery, support ingas an integral part of itself all of the socket except the outer metallic shell and cap. To one end of this porcelain body the lamp-terminals Y and D are attached. The drawings show these terminals adapted to Edison baselamps. The socket may be adapted to Thomson-Houston lamps by making the ordinary threaded plug for the inner terminal and a fiat ring replacing the flange of the outer terminal D. It may be adapted to the W'estinghouse lamp by making a V-shaped spring for the inner lam p-terminal and a beaded clampshell for the outer terminal. This porcelain body Bis formed with a large central cavity 0*, Fig. 7, to receive the circuit-breaking mechanism. This cavity is formed with shoulders or ledges at D upon which the contact-spring O rests when not in contactwith the tip A which spring is secured to the block in a recess at E The cavity E in which the spring O is fastened, is made deeper on the side next the center of the body to give the spring 0 a downward tension against the ledge D assuring certainty of the position of the contact and a maxim um break distance when the tip is turned to break the circuit.

C O are the conducting-wires. C leads through a hole I to a lateral recess E, in which are placed the wire terminal F and bindingscrew G,which is connected to the outerlampterminal D through its flange. The conducting-wire 0 passes through the hole I" to the terminal F, which is connected by means of the screw P to the mechanism-spring O,which is protected by an insulated leaf N of the same shape as the spring. This spring makes a contact with the tip of the circuitcontrolling key A when in a position shown by full line of Fig. 7 and by way of the frame-piece 13 and screw Z connects with the inner flexible lamp-terminal Y. When the handle H is turned in position of the dotted lines H, the circuit is broken between the spring 0 and the tip A In the keyless form of this socket (shown in the drawings) the screw P is connected bya strip of metal directly with the screw Z.

A is a ring of insulating material securely fastened to the outer lamp-terminal D, one method of fastening (shown in Fig. 2 at d) being effected by lancing the metal of the contact-shell D into the insulating-ring A at several points along its inner circumference. The insulating-earpiece L L, Fig. 8, made from flexible material, is lanced through at WV to more effectually insulate the wire terminal F, which passes through the opening thus made. The tips X X are lanced through to permit the passage of the flexible central contact Y and effectually insulate it and the lamp-contacts from the terminal of opposite polarity. This earpiece L L is held between the end of theporcelain body B and the flange of the terminal D andis fastened in position by the screws K, which hold the outer contact D to the socket porcelain body. The ear can be turned up, as shown in Figs. 2 and- 3, for drawing in and fastening the conducting-wires and can be folded into the ledges J J around the recess F F, completely in sulating these current-carrying parts from the outer metallic shell when the socket is inserted in the shell. By reason of its construction the socket-body cannot be forced into the outer shell if the ears L L are bent in the wrong way from their normal position. They are invariably forced into the ledge around the contact recesses when the socket is inserted in the shell. Neither can the carpieces L L be separated from the body portion without destroying the socket. The insulating-ring A being also permanently secured to the outer contact, it will be seen that the difficulties experienced with removable shell-linings and insulating devices separable from the body or from the shell are entirely obviated in my improved socket. It will also be noted in this socket that the insulated wire or cord for a considerable distance from the point where the ends are bared for attachment to the bindingscrews are surrounded by solid walls of porcelain't'. 6., the holes I Iand that the circuit -breaking points between the spring 0 and tip A are equally well protected by insulating material from the shell or outer metallic covering of the socket.

The flexible contact Y of my improved socket, Figs. 4 and 7, is formed of a small cup'of spring metal having its outer edge cut with triangular points, which are bent inward, forming a spring-bearing for the lampterminal and securing continuous tension against it, making the lamp less liable to jar out of contact.

In Fig. 9 I show my method of fastening the screw-shell contact D to the insulating body portion, which consists in expanding a nut or eyelet Vin the rim of the contact and threading it to receive the screw K. This is a cheap, effective, and very convenient method. The eyelet projects below the rim and allows the use of the screw with a variable thickness of the porcelain that will notproject too far throughthe contact-rim.

In Fig. 5 is shown my novel construction of the shell. The nut or eyelet S is expanded by an irregular punch into a similar hole in the edge of the shell. The nut or eyelet is then threaded to receive the locking-screw, upon which fits the bayonet-slot, similar to devices now in use, (not shown in the drawings,) in the edge of t-hecap M. These screws S S when gripping the cap extend into the recess in the body portion Q Q, holding the shell and body from turning upon each other.

It will be readily seen by one skilled in the art that this piece of porcelain can be made by a simply vertical acting die and that it is strong in all of its parts and otherwise easily molded, and the parts of the die are not liable to excessive wear, whereas everything in the socket except the outer shell is a unit when the socket is assembled. It can be quickly wired upon fixtures or other devices whereit is desirable to have the condi'lcting wires drawn tight after the socket has been screwed in place. The socket cannot be attached and wired without having all the parts etfectually insulated. The circuit-breaking mechanism consists of a long and very heavy bronze spring 0, insulated by the fiber strip N. The shoulder D in the porcelain cavity 0 tixes its motion and permits of the breaking of a very considerable current at a very much higher voltage than has commonlybeen used in this class of sockets. It is further noted that the same porcelain piece is adapted with slight changes of attachments to the manufacture of the three principle styles of sockets usedviz., the Edison, Thomson Houston, and Westinghouse. It is also adapted to keyless sockets of all of these patterns by the change previously noted. At the place-where the cord is knotted in the cap of the socket it is thoroughly protected and well removed from any abrading surfaces or current:- carrying parts. The method of passing the cord through the holes I 1 instead of through grooves in the edge of the porcelain prevents all opportunity of jamming or abrading the cord when inserting the socket in the shell.

Having thus described my invention, what I claim is 1. In a socket for incandescent lamps the combination, with a metallic outer shell of an insulating body portion, wire terminals carried thereby, and a sheet of insulating material fixed to said body portion adapted to cover said terminals.

2. In a socket for incandescent lamps the combination with a metallic outer shell, an insulating body portion having cavities for the contacts, and flexible insulating attachments on the body portion adapted to cover the contacts.

3. In a socketfor incandescent lamps the ICO IIO

combination of a metallic outer shell an insulating body portion having cavities for the contacts and flexible insulating attachments inseparable therefrom, adapted to cover the contacts, and a lamp-terminal with a complete fixed insulation.

4. In a socket for incandescent lamps, the combination of a metallic outer shell and insulating-body, supporting lamp-terminals, withinsulating-ears adapted to cover the wire terminals, rings and appurtenances inseparable therefrom com pletely covering all current-carrying parts and separating the same from the metallic shell substantially as shown and described.

5. 1na socket for incandescent lamps, the combination with an outer metallic shell of aninsulating-body preferably of pottery, having a central cavity for the reception of the circuit-controlling mechanism in one end, holes from the same end leading to lateral recesses containing wire terminals upon the opposite end, an insulating'strip adapted to cover said wire terminals when the body is inserted in the shell and adaptedto bend outward to give access to the terminals.

6. In a socket for incandescent lamps the combination with a metallic outer shell of an insulating-body having a central cavity for the reception of the circuit-controlling mechanism, acontact-spring within said cavity and an insulating-sheet covering said spring.

7. In a socket for incandescent lamps, the combination of an insulating-body preferably of pottery, having opposite cavities on one end, containing circuit-terminals, holes from the terminal cavities to the opposite end of the body, a complete insulating-ring permanently attached to the outer lamp-terminal and body, flexible insnlatingears permanently attached to the body adapted to insulate the circuit-terminals from the metallic shell when the body is within the shell and to expose the circuit-terminals for connecting the terminal wires when the bodyis separated from the shell, an outer metallic shell substantially as shown and described.

8. In a socket for incandescent lamps, the combination of an in sulating-bod y preferably of pottery, having in one end a central cavity for the reception of the circuit-controlling devices, and shoulders upon one end of the cavity for limiting the motion of the contactspring, holes from one end of the body, lateral recesses connecting with said holes and adapted to receive the wire contacts, a fibrous covering for the contacts when the body is inserted in the shell of the socket and capable of being turned aside when the body is out of the shell of the socket; a complete insulatingring fastened to the outer contactof the socket and a metallic outer covering or shell and cap substantially as shown and described.

9. In a socket for incandescent lamps the combination with a metallic outer shell, of an insulating-body carrying Wire terminals, and insulating-coverings for said terminals when the body is inserted in the shell and capable of being turned aside when the body is out of the shell.

10. In an incandescent-lamp socket, an insulating and supporting body constructed with two opposite cavities for the circuit-connecting screws and insulating-covers therefor, one of these cavities also enlarged for the screw connecting said block with the shell; two holes for two circuit-wires from the base to said above-mentioned cavities; a central excavation from one side of, and in the bottom of, the block nearly to the opposite side for the frame-piece, key-shaft, and contact block, and having recessed shoulders for holding and connecting the contact-spring O and its insulator within the lower surface of the block; and a hole in the top of the block for the contact-spring Y; all substantially as described and shown.

11. In an incandescent-lamp socket, the combination of an insulating-block constructed substantially as described and shown, in combination with a circuit-controlling key and metallic support and spring therefor inclosed within said block; a metallic lamp-contact connected and held bya screw upon one end of said block, a spring recessed and held in the opposite end of said block above its central cavity an d-having an insulating-cover therefor and circuit-terminals for the two wire circuits, one connecting permanently with the socket-shell and the other with the said insulated spring, and all being adapted to en'- able the circuit-controlling key to make contact with said spring to open and close the circuit; substantially as described and shown.

12. In an incandescent-lamp socket,in combination with an insulating-block and circuitcontrolling key, circuit-terminals and a metallic shell mounted upon said block, an insulating shell or rim of fiber connected with depending flexible ears adapted to cover the recesses containing the circuit terminals; substantially as described and shown.

13. In an incandescent-lamp socket the combination of an insulating-body having a recess therein for inclosing the circuit-controlling devices, a contact-spring arranged over said recess and supported on shoulders formed on said body, and a circuit-controlling key for engaging said spring.

14. In a socket for incandescent lamps a body portion of pottery with a hole extending partially through from one end for the conducting-wires, a recess extending in from the other end for the wire terminal, with a lateral opening connecting the two, substantially as shown and described.

15. In a socket for incandescent lamps a body portion B formed with contact recesses F F extending in from one end, holes I I formed from the other end, an opening between the hole I and the recess F as shown and described.

16. An insulating-body for'incandescentlamp sockets provided with a cavity in one ICS end for thecircuit-controlling devices, holes I, 1 extending from said end, lateral recesses F, F, extending from the opposite end and opening into said holes.

17. In a socket for incandescent lamps, the combination of a bodyportion having exposed Wire contact in lateral recess on the side of said body portion With a flexible fiber sheet adapted to close over and separate the wire terminals from the metallic shell and covering.

18. In a socket for incandescent lamps a fixed insulated lamp-terminal formed by lancing at several points the metallic contact into an insulating-ring surrounding it, substantially as shown and described.

19. In a socket for incandescent lamps the combination of an insulating-body, a lamp terminal shell provided with a flange 01' rim, a nut expanded in a hole in said flange and screw-threaded, a screw passing through said body and engaging said nut.

20. In a socket for incandescent lamps, an insulating-block with cavities for the circuitterminals and circuit-controlling mechanism with insulating-ears and appendages, adapted to receive fittings for Edison, Thomson- Houston, and Vestinghouse lamps, substantially as shown and described.

21. In a socket for incandescent lamps, an insulating-block with cavities for the circuitcontrolling mechanism with insulating-ears and appendages adapted to insulate all current-bearing parts, an outer screw-shell contact, an inner flexible contact, substantially as shown and described.

22. In a socket for incandescent lamps the combination of an insulating-body, lamp-terminals carried thereby, a sheet of insulating material provided with tips X, X, for separating the lam p-terminals of opposite polarity.

23. In a socket for incandescentlamps the combination of an insulating-body, a socketshell, a sheet of insulating material between said shell and base, provided with an opening for the passage of the central contact, and 

